Possible ovalised headtube?

Ben6899

Dolan Preffisio, aluminium frame.
Stock, integrated Alpina headset (fitted since new in early 2012) with cartridge, chamfered 36x45 bearings.
Fork is carbon with aluminium steerer. Feels solid.
The bike is my dirty option - if the roads are shitty, this is the bike I use. I ride all year round (with Crud guards in deep winter).

The other day, mid-ride, I felt some play in the headset (a tiny amount) and so 'tightened' everything back up at the cafe stop, using my multitool. When I got home, I loosened everything and re-'tightened' using a torque wrench.

I know what I'm doing so this isn't a "did you loosen the stem bolts?" type thread.

I have since ridden the bike twice and had to re-'tighten' the headset after both rides. The first occasion, I dropped the forks and cleaned everything up. Things looked pretty damn clean, considering the use this bike sees.

So I did a bit of Googling along the lines "headset keeps loosening" and found a good handful of articles and forum threads about ovalised/ovalized headtubes - caused by loose headset bearings being allowed to 'bang' against the inner walls of the headtube through the owner's poor maintenance and riding around with a loose headset.

1. Does anyone have experience of this? Any good workarounds for someone on a budget?
2. Is it common?
3. (I'm OCD about my headsets and the slightest sign of the adjustment being out, it's all sorted out i.e. I don't ride around with loose headsets). Could it just be the bearings are in fact in need of replacement?
4. If the news is bad, do you fancy selling me a cheap winter frame?

I appreciate your thoughts.

badgermilk

Why don't you measure the frame to make sure it's still round. You need some internal vernier calipers

Ben6899

I don't have any vernier calipers.

keezx

If the headtube is worn on the inside by moving bearings , you would be able to see it.
When the parts where the bearings make contact show no signs the cause must be someting else:
- Bearings worn itself.
-Starnut loose.

Don't think the frame is knackered, i've ridden alu bikes with integrated headsets a long time (and still do) and never had a single problem with them., with the last one I build it up 18 months ago and since then never even had to touch it. (appr. 10000 km ridden)

gloomyandy

What sort of steerer tube is it? I had a problem very much like this that turned out to be the "bung" in the carbon steerer tube being pulled up by the cap. I also had a clubmate that had this problem for weeks, finally turned out that the steerer tube (alloy) was being pulled out of the (carbon) forks which is rather scary!

Monty Dog

'Walking' fork bung would be my first call - try a different one to see if it stops

g00se

As the steerer is aluminium, tighten the stem bolts a bit more.

Just so you know, I've had my stem on the carbon steerer at 5nm and loosened. Did it to 6nm and it held fine.

You could also try a stem with greater contact area (maybe shimmed) and even try carbon paste, even if it is aluminium.

Ber Nard

Hmm... my Preffisio, which is getting on a bit now, has started to do the same thing.

The headset's only a couple of years old but it's possible it's worn.

Unless I'm missing something, I don't buy the expander bung theory: If the headset is properly adjusted and the stem bolts are tight, surely the bung becomes redundant and could even be removed?

I'm inclined to blame my headset spacers. I have 3x 5mm spacers beneath the stem. I suspect they may not be exactly square on top of one another and turning the bars causes them to shift and open a slight gap.

I have vernier calipers, a day off and not much to do so I may strip the front end and see what's what.

Ben6899

Thanks for the comments.

It's an aluminium steerer with a star nut. That could be slipping, but I can manage to initially set sufficient preload on the bearings - after the stem bolts are tightened, it becomes redundant. Right?

So on Sunday, I reset everything and torqued the stem bolts to an indicated 6Nm. I'll monitor.

Ber Nard. Let me know how you get on.

gloomyandy

Although in theory the top cap/bung is not used once the stem is tight it does provide extra load on the stem stopping it from moving. So if the stem is not actually tight enough then the cap will be helping stop any movement, but if the cap can move then... well you get the picture. This is what I think was happening in my case. A combination of carbon paste, slightly higher torque on the stem bolts and expanding the bung a little more fixed it!

Ber Nard

Right, I've had a look at mine and the head tube is perfectly round so I think I can rule that out.

The lower bearing is a little graunchy but not excessively worn and there's no play when the bearings are in the frame.

I've got a single 15mm spacer on order to see if the multiple spacers are the problem. I'll wait until I've put a good few miles on it before fitting to see if the problem has already gone away. Maybe cleaning and refitting everything will have worked.

If all that fails, I can only think something isn't square and maybe the head tube needs facing.

Ben6899

I think ovalisation is rare, especially on frames as new as ours.

I am hoping tighter stem bolts (and maybe some carbon assembly paste) will solve it.

DeVlaeminck

Also had the problem with the bung, mine was on a Focus and turned out others on here had had the same. I would check that first.

keezx

There is no bung.

veronese68

Ben6899 wrote:

Thanks for the comments.

It's an aluminium steerer with a star nut. That could be slipping, but I can manage to initially set sufficient preload on the bearings - after the stem bolts are tightened, it becomes redundant. Right?

So on Sunday, I reset everything and torqued the stem bolts to an indicated 6Nm. I'll monitor.

Ber Nard. Let me know how you get on.

Right. That's assuming the stem bolts are tight enough of course.